The invention relates to a process for producing thermoformed articles such as food packagings or parts thereof with a mechanical weakening between adjoining functional areas, which, for utilization by a user, can be at least partly separated at the mechanical weakening, in a thermoforming die having an upper die and a lower die, the mechanical weakening being introduced with a three-dimensional extension during the period of time during which the material to be formed is located in the thermoforming die, and a thermoforming die for implementing the process.